Ms Grayspence has lived in the house on Sydney's north shore for more than 60 years.

"Because my father was at Gallipoli ... my mother was able to borrow from the War Service Department enough money to build a house on an old tennis court," she said.

"It's an empty nest now, everyone's left, but I am here and I want to stay here."

Treasurer Joe Hockey says he wants a national conversation about welfare payments and how sustainable the current system is.

The age pension accounts for about one-tenth of the federal budget, and some economists are calling for the means test to include pensioners' homes.

Economist Stephen Anthony is among those advising the Government to consider a pensioner's primary residence.

"If you included a means test, and only pay the pension to someone who had a house worth less than $1 million ... you would save $1.2 billion right there," he said.

The suggestion has the support of Cassandra Goldie from the Council of Social Service, who says that is a better option than raising the pension age or changing indexation.

"We do think the assets test is too generous ... we should taper that back," she said.

"Right now, you can own your own home, a multi-million-dollar home and have over a million [dollars] in assets and still be eligible for the part pension. We don't think that's fair."

But Ms Grayspence says it is the approach of the Abbott Government that is lacking fairness.

"I think most of them, they've got themselves, they've inherited something, they can't cope and they're going from the sublime to the ridiculous to think that they can get enough money out of the elderly."